Is Your Cardio Killing Your Results?

Results like these don't come from endless cardio sessions. Just saying...

There is a delightful older woman at my gym who spends 60 minutes on the treadmill each day. She walks at a moderate but steady pace, and complains endlessly about the lack of results she is getting from her workout. And yet she continues to do more of the same. Like many gym goers, her cardio program is killing her results.

There are a few reasons why endless cardio sessions don’t serve you well:

  1. If you’re doing more than 45-minutes of cardio, you’re entering into the “danger zone” at which point your body will start burning muscle - not fat.
  2. Since long sessions of monotonous cardio result in muscle loss, the effect is a decrease in the body’s metabolism (as muscle is a large driver of your metabolism). In other words, the body will burn fewer calories throughout the day because of muscle loss. For some people, this could even mean gaining weight.
  3. It’s time consuming! 60-minutes on the treadmill is time better used elsewhere… like in the free weight or strength training section of your gym. Or even time better spent doing some fitness research, like reading this blog. 🙂

There are two quick fixes for endless, monotonous cardio sessions:

  1. Interval training. I keep my cardio sessions relatively short - but extremely effective - by using interval training. In a nutshell, it’s all about varying between intensities on cardio machines - from medium intensity to high intensity. I jog for 90 seconds and then sprint for 60. After 15 minutes, I’m totally beat! It burns more calories than long cardio sessions, and has a huge positive effect on metabolism.
  2. Strength training. I can’t say it enough: Any comprehensive fitness program needs to include both cardio and strength training. If you are just doing cardio, then you are killing your results. Everyone needs to hit the weights as well - especially if your goals include weight loss.

Are you in a long, monotonous cardio rut? Tell us about it in the comments below. And I hope this post can be a light at the end of that results-killing tunnel!

And note: Today is the last day to save 25% off of my Ultimate Guide to Working Out - and it’s the last chance to get Underwear Yoga as a free gift. Through my program, we’ll create a fitness program that is customized to your results. Use discount code “buddy” during checkout to save 25%.

About Davey Wavey

Davey Wavey is a certified personal trainer and YouTube sensation with more than 250 million video views. For Davey's fitness tips and secrets, sign up for his free monthly newsletter - or download any of his affordable and effective workout programs.


  1. I think the backlash against steady state cardio is too strong. Granted, endless treadmill sessions do nothing to build muscle. But as you stated, it’s lifting weights that will stimulate hypertrophy. And while HIIT certainly has benefits, I tend to think that it could result in CNS stress (overtraining) or compromise recovery from lifting, because it provides similar stresses to the legs. Steady state cardio, while a bit time consuming (and perhaps boring) can be a useful means of stimulating blood flow, and thus facilitating recovery. It works much better as an off day “workout”, in that regard. This isn’t an either/or proposition though. One can incorporate lots of things in to their routine — and probably should. Just keep in mind, even elite track athletes and distance runners keep their “hard” runs to no more often than 2-3 times a week.

  2. Hey DW,

    Love your blog(s) and posts. I’m wondering about this particular post. For the last few months, I’ve built a routine where I work out 3-4 times a week for about an hour each time. Sometimes I get a 5th day in too. I’m now rethinking the balance I’ve struck between the two categories, cardio and weight training. I’d like to lose say 10-15 pounds and get a bit of definition/shape. I’m almost 30 so I figure its time to honor thy body. And who wouldn’t want nicer pics and bigger arms.

    That said, I usually spend two days doing about 60 minutes of cardio which I’ll scale back according to this post, and I spend alternate days doing 30 or so minutes of weight training and another 30 doing cardio.

    I’m wondering what you think is best or what variation you’d suggest?

    PS. Been doing interval training. Crazy how I feel that cardio all day.

  3. Wow! I honestly had no idea! I’ve been going to the gym for about a month now, and every day I always start off with 30-45 minutes on the treadmill at a steady pace. Who’d have thought it was actually doing more harm than good! I’ll make sure to change it up a bit from now on. Thanks Davey!

  4. I was well over 200 pounds in highschool and at 5’4 thats HUGE. I became addicted to cardio in college and dropped 70 pounds in 5 months. That was 10 years ago! I can say that I am STILL addicted to cardio but know to limit it to 45 minutes or less and love interval training. Its intense and great for calorie burning.

    I also know the importance of mixing it with strength training, but the heart is a muscle and it needs lovin too which is why I will never neglect cardio.

    That being said, I have managed to keep off the weight and gain a healthy amount of lean muscle. I am 29 years old and at 5’4 I am a solid 147 with a 9% body fat (sometimes less sometimes more depending…but NEVER over 10%)

    Best of luck to anyone working hard to maintain a healthy lifestyle, I know you can do it!

  5. I agree with Alex that cardio is the keystone of good health: take care of the pump and the plumbing first and foremost. <120/80 is much more important than a six pack and improves the lipid profile. I tell people if they find themselves with only a half an hour to exercise, they will derive the most health-benefit from cardio.

    Personally I think it's important to have some kind of a protein-rich meal, like a muscle milk-type preparation, after an intensive cardio work-out. This will limit the muscle break-down (catabolism).

    Also I always do some kind of resistance exercise, usually a medley of push-ups and pull-ups after I run. This also helps preserve muscle-mass.

    That said, Davey is correct to point out that pure cardio is not the way to go if you're looking to loose weight. You need a program that integrates cardiovascular and strength conditioning as well as diet. It is important to keep in mind that muscle weighs more than fat, so you may see cosmetic improvement without having to undergo dramatic weight loss. And of course strength conditioning also increases bone mass/weight, which is a good thing, especially for women. Women need to work out with weights more than men, actually.

    Not surprisingly, marathoners usually 'run' (no pun intended) at about 15% body fat. You notice that many marathoners have little guts. That's their gas tank. The gut is where most of the fat that feeds the endurance (aerobic, slow-twitch) muscles of you lower body is stored.

    Diet: I once saw a moderately obese woman in clinic who couldn't understand why she couldn't loose weight. She said all she ate were salads and she rode her exercise bike an hour a day! What she was doing was essentially starving herself, and in the process turned on her 'thrifty genome': her body turned all nutrition straight to fat. A balanced diet, including fat, is important for maintaining a healthy weight. If you don't eat fat, your body is perfectly capable of making it. Remember that cows eat grass the next time reach for the half-and-half or dive into a beautifully marbled aged sirloin!

  6. I run 3 or 4 times a week. My shortest I ever do is 4 miles and the longest about 20 miles.

    My question is that all of my runs comprise of at least one hill that is half a mile to a mile long at 12% or more incline. Does this part of my run count as strength training for my legs as well as cardio?

  7. “If you’re doing more than 45-minutes of cardio, you’re entering into the “danger zone” at which point your body will start burning muscle – not fat.”

    Pure broscience.

  8. I’m 5ft 4 in high and I weight 83 kg. My goal is to lose 20 pounds in 5 months. My fitness instructor won’t let me touch the weights instead he has me doing cardio for 2 HOURS. I can’t begin to explain how boring it is to walk on the treadmill for 1 hour straight. What should I do?

  9. It’s truly a great and useful piece of info. I am satisfied that you just shared this helpful inbfo with us.
    Please keep us informed like this. Thank you for sharing.


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